Tear layer disruption results in a decrease in the modulation transfer function (MTF) for the eye. Since the tear layer is the first refracting surface of the eye, its disruption can also result in a change in contrast sensitivity, visual acuity, and aberrometry. Previous work has demonstrated that higher order aberrations increase 1.44 fold after the tear film breaks up in normal subjects. Dry eye subjects demonstrate a significant increase in higher order aberrations (i.e., total S3+4+5, spherical-like S4, and coma-like S3+5) when compared to normal subjects. This has been interpreted to be the result of increased tear irregularities in the dry eye subjects.